Oscillator roller for printing presses

ABSTRACT

An oscillator roller for a printing press which achieves a superior breakup and distribution of the substances with which it comes into contact, and which comprises an elongated cylinder having one or more spiral bands or raised lands formed along its surface and which extends longitudinally therealong. When more than one spiral band or land is utilized, they are normally found in opposition to each other. The oscillator roller when used in the dampener of an offset printing machine is normally in surface-to-surface contact with one of the form rollers, as referred to, and is operable to distribute the dampening solution evenly over the surface of the form roller prior to its application to the printing plate. The oscillator roller may also be used in like manner in the inking system of a lithographic or conventional printing press to provide substantially even distribution of the ink prior to its application to the printing plate.

United States Patent [72] Inventor Paul R. Kantor Cleveland, Ohio [211 App]. No. 732,302 [22] Filed May 27, 1968 [45] Patented Oct. 19,1971 [73] Assignee Kantor Press Kontrols, Inc.

Cleveland, Ohio [54] OSCILLATOR ROLLER FOR PRINTING PRESSES 9 Claims, 5 Drawing Figs. [52] 11.8. C1 101/148, 101/350, 29/121 [51] Int. Cl B411 7/36 [50] Field of Search 101/147, 148, 205-209, 348, 349, 350-352; 29/121; 118/261 [56] References Cited UNITED STATES PATENTS 1,793,202 2/1931 Wolstenholne 29/121 2,199,228 4/1940 Obenshain et a1. 29/121 X 2,309,585 1/1943 Aardock 29/121 X 2,530,282 1 1/1950 Brodie et al. 29/121 96,480 11/1869 Phelps 101/187 223,981 2/1880 Bissinger 10l/V. R. DIG. 255,704 3/1882 Trueman et a1 101/340 X Primary Examiner-J. Reed Fisher Attorney-Baldwin, Egan, Walling & Fetzer ABSTRACT: An oscillator roller for a printing press which achieves a superior breakup and distribution of the substances with which it comes into contact, and which comprises an elongated cylinder having one or more spiral bands or raised lands formed along its surface and which extends longitu dinally therealong. When more than one spiral band or land is utilized, they are normally found in opposition to each other. The oscillator roller when used in the dampener of an offset printing machine is normally in surface-to-surface contact with one of the form rollers, as referred to, and is operable to distribute the dampening solution evenly over the surface of the form roller prior to its application to the printing plate. The oscillator roller may also be used in like manner in the inking system 01' a lithographic or conventional printing press to provide substantially even distribution of the ink prior to its application to the printing plate.

PATENTEnnm 19 ml 3,613,575

sum 1 or 2 SPIRAL ROLLER\ INVENTOR PAUL R. KAN TOR SHEET 2 BF 2 PATENTEDum 19 I971 INVENTOR PAUL R. KANTOR OSCILLATOR ROLLER FOR PRINTING PRESSES This invention relates generally to printing presses in the graphic arts field and more particularly to a new and improved oscillator roller for use in printing presses. In the graphic arts field a condition sometimes occurs which is known as ghosting which is the creation of an unwanted repeating of a printing image particularly one which has a combination of solids, reverses or screens. When such ghosting condition occurs, it is necessary to withdraw and discard the printed material.

As is also well-known in the art, in conventional and photo offset press machines ink and water oscillator rollers are utilized, their primary objective being to distribute and thin out the film of ink and/or water upon the surface of the rollers which subsequently apply said ink and/or water to the printing plate. These oscillator rollers may also have a physical sideways motion, anywhere from a few inches to as much as one foot which motion is also used to effect distribution of said ink and/or water.

The oscillator roller of the present invention when incorporated into a conventional printing press and/or in a photo offset press achieves superior distribution results over the conventional rollers heretofor used and is particularly operable to substantially completely prevent any ghosting conditions.

This is accomplished in the oscillator roller of the present invention by providing a plurality of spiral bands on the surface of the roller, either recessed or raised with respect to said surface and which extend longitudinally therealong in opposite directions to each other.

When this roller is placed into operative contact with the inking or dampening rollers of the printing press, it causes the ink or water to be smoothly and evenly moved and distributed from one end of the roller to the other end and back again by virtue of the spiral bands. This results in superior ink coverage on all jobs and also superior water control.

While there is a constant emulsification of the ink on lithographic presses, it is especially true when running sheets of a smaller size than the press was designed for, there is a tendency for the water to accumulate on the ends of the dampening rollers of the press outside of the edges of the sheets being run thereof which, in time, works itsway into the inking system and causes emulsification thereof. This is a familiar condition encountered in lithographic presses. Heretofore, ink manufacturers have concluded that under the most ideal" conditions, 25 percent of the weight of the ink on the rollers of a lithographic press which has been run for 45 minutes to an hour consists of the fountain solution suspended as tiny droplets throughout the ink. This hygroscopic or water absorbing tendency of the ink is further compounded by the roller arrangements found in lithographic presses. These rollers literally beat and mill the fountain solution into the ink.

Other more recently devised dampening systems use an alcohol mixture in the fountain solution in an attempt to alleviate this problem, which has been accomplished to some extent. However; alcohol is expensive, toxic, causes certain inks to bleed and it attacks the images on the printing plate.

The oscillator roller of the present invention is operable to allow the fountain solution to escape from the ink by virtue of the recessed portions of the roller. This results in less emulsification in the dampening and/or the inking system and also alleviates the host of problems associated with such emulsification as is well known to those familiar to the art. The oscillator roller also eliminates this emulsification condition because the spiral recessed bands completely distributes the film of water evenly across the entire length of the dampener roller with which it is in contact, said recessed portions or bands also allowing the water to escape from the ink. Likewise, on lithographic presses in which dampening systems where the water and ink are combined on one roll, the spiral oscillator roller of the present invention works at its peak efficiency.

Dampening and also ink settings become less critical because of the uniform distribution of the ink and/or water by the oscillator roller of the present invention.

it is therefore a primary object of the present invention to provide a new and novel oscillator roller which produces completely uniform distribution of the ink on rolls of printing presses.

Still another object of the present invention is to provide an oscillator roller which produces completely uniform distribution of ink and dampening solution on the rolls of lithographic printing presses.

Still another object of the present invention is to provide new and novel roller means which eliminates the condition referred to in the art as ghosting.

Additional objects and advantages of the oscillator roller of the present invention will be apparent to one skilled in the art to which it pertains and upon reference to several preferred embodiments thereof which are disclosed herein and which are illustrated in the accompanying drawings, wherein:

FIG. 1 is a fragmentary, schematic illustration of the arrangement of the inking and dampening rollers used in a conventional lithographic printing press and which shows the several locations in which the oscillator roller of the present invention may be disposed in such arrangement;

FIG. 2 is a schematic perspective view of an oscillator roller incorporating the concepts of the present invention with the oppositely progressing spiral bands shown in diagrammatic form on the surface thereof;

FIG. 3 is a fragmentary perspective side view of one embodiment of oscillator roller of the present invention and which shows the roller surface formed with two spiral recesses which progress in opposite directions to each other along the roller surface and at preselected angles to each other;

FIG. 4 is a fragmentary perspective side view of another embodiment of oscillator roller in which spiral lands are formed on the roller surface, and;

FIG. 5 is a fragmentary perspective view showing the oscillator roller in contact with a roller of a printing press.

With reference now directed to FIG. 1 there is herein shown part of a typical assembly of a conventional photo-offset printing press comprising a plate cylinder 9 upon which the printing plate is mounted. As will be understood, the plate cylinder is rotatable in a counterclockwise direction as shown, to carry the printing plate past the water (dampening solution) carried within dampener unit identified schematically at 10, and then past the inking unit as also identified schematically at 11.

In the manner also well known, water (dampening solution) is applied to the nonprinting areas of the printing plate and ink is applied to the printing or image areas of said plate whereafter the plate is effective to print the image onto a suitable printing material.

The cylindrical rolls as identified at 7 schematically represent the conventional oscillator mechanism for supplying the printing ink to the printing form rolls which in turn supply the ink to the printing plate as the same is rotated with the plate cylinder, said plate being periodically brought into engagement with the said inking form rollers numbers 1 thru 4, thus occurring once per each printing operation.

In like manner, the cylindrical roll as identified as water form roll No. l is schematically representative of the dampening mechanism which is operable to apply a quantity of dampening solution to the printing plate as the same is rotated with the plate cylinder.

As is known in the art, the conventional ink or water oscillator rollers do not do a thorough job of breaking up the ink or water film upon them. This is especially true when running sheets that are smaller than the press was designed for. For example, an 8%Xl l-inch sheet can be run on a l7 22-inch lithographic offset printing press and in doing so, the sheet would only remove the ink and water across an I l-inch width, leaving approximately 5 inches on each side of the press for water and ink to accumulate. As mentioned before, the conventional oscillators cannot distribute this film of ink or water to prevent this buildup on the ends of the rolls of the dampening systems. There are many other disadvantages known to those connected with the art to which this invention pertains but the aforementioned problem is one of the foremost.

The oscillator roller of the present invention, as is identified by the reference numeral 8, is adapted to be placed into either the dampener or inking device 11 in a plurality oflocations several of which are depicted in FIG, 1. With the oscillator roller 8 thus disposed in one or several of said locations, the water (dampening solution) and ink are evenly distributed by said rollers across the surface of the roll with which it is in engagement being thus effective to provide for a substantially equal application of said water (dampening solution) and ink to all applicable portions of the printing plate.

With reference now directed to FIG. 2, the oscillator roller 8 incorporates the concepts of the present invention and is shown somewhat-in diagrammatic form and is seen to comprise a cylinder 15 having a pair of spiral bands 16 and 17 formed thereon and which may be recessed or raised with respect to the roller surface 18.

Spiral bands 16 and 17 are formed of opposite lead to thereby cross each other at spaced intervals along the roller surface as depicted at 21.

At each end of the roller closely adjacent the edge thereof the spiral bands 16 and 17 are connected to each other as shown at 23 to thereby form a closed spiral which, because of its geometry a path can be traced longitudinal along the roller in one direction for example to the right as seen in FIG. 2, upon spiral band 17 and then in the opposite direction or to the left upon spiral 16. As will be realized this cyclic path is automatically repeated, the reversal of the path being accomplished by means of the connected ends of the spiral bands.

In the embodiment of spiral roller shown in FIG. 3, the spiral bands 16 and 17 are recessed to thereby form spacedapart diamond-shaped islands 30. The surface of the roller at the ends of said roller and of the islands 30 represented by the shaded portions may be formed of an ink receptive material such as copper, brass or teflon, whereas the surfaces of the recessed bands 16 and 17 may be formed of a water (dampener solution) receptive material such as chromium; however, it is contemplated that the said shaded portions may be formed of water receptive material and the recessed portions of ink receptive material. It is also contemplated that the complete roller surface, spiral recesses and islands may be formed of either ink or water receptive material.

As also seen in FIGS. 2 and 3, the lead angle of spiral bands 16, 17 is about 70, however, said lead angle may be less or greater in its lead angulation, the basic requirement therefore being that it is effective to move the ink and/or water (dampening solution) over the surface of the roll with which it is in contact.

It has been found in actual practice that oscillator rollers having a relatively high lead angle, for example 70, are best for use in the inking system or on a dampening system which may also carry an ink film.

The actual lead angle selected will depend primarily upon the diameter of the roll with which it is in contact, the rotational speed of the said contacted roll which is very important in web-offset and where the oscillator roller is to be used and with which dampener system, ink and/or water.

In actual practice, oscillator rollers having the construction shown in FIG. 3 have been made with a lead angle within the range of approximately 6075 for the recessed spiral bands 16 and 17, and a width of one-fourth inch and a depth within the range of 0.001 inch to 0.050 inch.

With reference to FIG. 4, there is herein shown an oscillator roller of the present invention in which the spiral bands 16 and 17 are raised lands to define spaced-apart diamond-shaped recesses as identified at 32.

The surfaces of the roller as shown in FIG. 4 which are shaded comprising the ends of the roller and the raised spiral lands may be formed of ink receptive material such as copper, brass or Teflon, and the surfaces of the diamond-shaped recesses 32 may be formed of a water receptive material such as chromium. However, the surfaces of said roller may be selectively formed of ink or water receptive material in the manner described in the embodiment of roller in FIG. 3.

The lead angle of the raised spiral lands may be the same magnitude as the spiral recesses in the roller of FIG. 3.

The roller construction of FIG. 4 is preferably used with the ink rolls in lithographic or conventional presses. Also, on conventional presses such as a letter press where water is not used, the roller of FIG. 4 is preferably used inasmuch as the need for water receptive areas such as recesses 32 is substantially eliminated, and it is desirable to have the spiral bands 16, 17 as raised lands so as to be effective to distribute the ink on said roll.

Further, when the roller of FIGS. 3 or 4 is used in the inking system of a conventional printing press, the depth of the recessed portions-spiral recesses 16, 17 of FIG. 3 and diamond-shaped recesses 32 of FIG. 4-may be made substantially deeper, as for example 0.0l0 inch deeper, as compared to the depth of said recesses when made on a roller for use in a lithographic press.

The manner in which the oscillator roller is intended to be in contact with a roll R of the ink and/or water dampening unit ofa printing press is best seen in FIG. 5. Merely for illustration the embodiment of oscillator roller of FIG. 3 is shown herein.

With the oscillator roller being rotated in a clockwise direction as shown, and the roll R in the opposite direction, the recessed spiral band 16 is effective to carry the water (dampening solution) to the right whereas the spiral band 17 is effective to carry the water to the left. Likewise, at the intersection 21 of said recessed bands 16, 17 the water may transfer from one band to the other. And, as the water reaches the ends of the roller, it is reversibly carried back along the surface of said contacted roll by the other of said spiral band. As a result, the water (dampening solution) is in a constant state of motion along the surface of the contacted roll. Further, the edges of the spiral bands 16, 17 as well as the edges defining the diamondshaped islands 30 are operable to cut up the ink on the surface of the contacted roll R and move the same constantly to and fro along the surface of said roll so as to distribute the ink substantially evenly over said roll surface.

In like manner, when using the oscillator roller of FIG. 4, the spiral lands are effective to carry the ink on the contacted roll substantially constantly along its surface to effect even distribution therealong.

Having thus described several preferred embodiments of the oscillator roller of the present invention it will be apparent to one skilled in the art to which it pertains that various modifications, changes and combinations of elements thereof may be made without departing from the inventive concepts thereof as are defined in the claims.

What is claimed is:

1. In a printing press having a printing plate and roll means for selectively applying ink and water to said plate, an oscillator roller mounted in said press and in operative engagement with said roll means, a plurality of spiral bands formed on said oscillator roller, at least two of said bands being opposite in longitudinal progression along the surface of said roller intersecting each other at spaced points along said roller, the ends of said two bands at each end of said roller connecting with each other by means defining a closed loop continuation of said bands adjacent each end of said roller to define a continuous cyclic path by which the ink or water may be selectively moved by one of said two bands in one direction longitudinally along said roller and then through said closed loop continuation of said bands and by the other of said two bands in the opposite direction longitudinally along said roller.

2. In a printing press as defined in claim I, and wherein the spiral bands are recessed with respect to the surface of the oscillator roller.

3. In a printing press as is defined in claim 2 and wherein the depth of the recessed spiral bands is in the range of 0.001 to 0.050 inches.

4. In a printing press as defined in claim 1 and wherein the spiral bands define interspaced recessed portions on said roller.

5. In a printing press as defined in claim 4 and wherein the surfaces of the spiral bands are formed of an ink receptive material.

6. In a printing press as is defined in claim 1 and wherein the surface of the spiral bands are formed of a water receptive material.

7. in a printing press as is defined in claim 1 and wherein the 8. In a printing press as is defined in claim 1 and wherein the surface of the oscillator roller is formed of a water receptive material.

9. In a printing press as is defined in claim I and wherein the surfaces of the oscillator roller interspaced between the spiral 5 lead angle of the Spiral pands is within the range of to bands are formed of an ink receptive material. 

1. In a printing press having a printing plate and roll means for selectively applying ink and water to said plate, an oscillator roller mounted in said press and in operative engagement with said roll means, a plurality of spiral bands formed on said oscillator roller, at least two of said bands being opposite in longitudinal progression along the surface of said roller intersecting each other at spaced points along said roller, the ends of said two bands at each end of said roller connecting with each other by means defining a closed loop continuation of said bands adjacent each end of said roller to define a continuous cyclic path by which the ink or water may be selectively moved by one of said two bands in one direction longitudinally along said roller and then through said closed loop continuation of said bands and by the other of said two bands in the opposite direction longitudinally along said roller.
 2. In a printing press as defined in claim 1, and wherein the spiral bands are recessed with respect to the surface of the oscillator roller.
 3. In a printing press as is defined in claim 2 and wherein the depth of the recessed spiral bands is in the range of 0.001 to 0.050 inches.
 4. In a printing press as defined in claim 1 and wherein the spiral bands define interspaced recessed portions on said roller.
 5. In a printing press as defined in claim 4 and wherein the surfaces of the spiral bands are formed of an ink receptive material.
 6. In a printing press as is defined in claim 1 and wherein the surface of the spiral bands are formed of a water receptive material.
 7. In a printing press as is defined in claim 1 and wherein the surfaces of the oscillator roller interspaced between the spiral bands are formed of an ink receptive material.
 8. In a printing press as is defined in claim 1 and wherein the surface of the oscillator roller is formed of a water receptive material.
 9. In a printing press as is defined in claim 1 and wherein the lead angle of the spiral bands is within the range of 60* to 75*. 